Michael Welzl wrote:
People are different. I'd be more than happy to let my MUA
even silently delete past:
* talk announcements
* CFPs
* special offers
* "out of the office messages"
(I'd happily just delete special offers and out of office messages,
whatever the date is...)
The problem is that you don't know what an 'expired' message is about
unless you read it.
People don't always do things right. So, a mailing list admin might well
set up a 'you have 3 days to authenticate your subscription' message
with an expiry date, or someone might send you a bill payment reminder
with an expiry date of when it's due or whatever. You can be sure
someone will use it in a way YOU don't want them to use it or think it
should be used (or even ways that any standard prohibits). That's just
the way people are... The amount of badly formed non-spam messages we
receive is incredible, and the MIME/RFC822 standards have been around
for years. If people can't get that right even now, you can guarantee
that people will use 'expire' in an inappropriate way.
So, would you still be happy to have your MUA silently delete expired
messages?
AFAICS, the only safe way to use 'expire' would either be for it not to
move/delete messages at all (in which case, what's the point) or to have
different rules handling expire differently from different senders (when
you know how THAT sender uses it), but this would only be useful if you
repeatedly got expired messages from particular people (which is doubtful)
(I do wonder, how important is this anyway? How often do you receive
messages after they would have expired? The only time I can think it
would be even slightly useful is if you've just come back from a
vacation and haven't checked your mail whilst you've been away, but then
a few CFP or talk announcements is going to be irrelevant amongst all
the other thousands of semi-junk messages you'll have received!)
I don't have a massive problem with an 'expires' header, I just see it
as, at best, pointless, and at worst, dangerous in the hands of an
unthinking user (of which there are many using the Internet).
--
Paul Smith
VPOP3 - POP3/SMTP/IMAP4/Webmail Email server for Windows